Listen (and stop listening) to player events.

listen-for-events.js

var player = videojs('player');

// an event listener is a function that (optionally) takes an event argument
function playingListener(event) {
  console.log('Look at me, I know how to listen for video events!', event);
}

// register the event listener
player.on('playing', playingListener);

// unregister the listener
player.off('playing', playingListener);